Ok, emailed with Dow Corning. They said that Disney uses DC 795 on their tanks. They also said that they use a primer in some applications. Anyone used a primer in a silicone to stone application?
It looks like Oddball had the winning answer, no surprise there...
Just yesterday I was cleaning out my classroom and i think I found the manual for your tank.
It is in mint condition - pretty cool find, I thought. It is 32 pages long with eight chapters! These days you don't get anything but a sticker on the tank.